Manchester United look unstoppable with Wayne Rooney in the mood

Wayne Rooney's awe-inspiring display against Aston Villa augurs well for Manchester United – as long as he stays fit and firing. Photograph: Jon Super/AP

Manchester United reached a milestone with their comfortable victory over Aston Villa last night. They are unbeaten for 29 league games, which equals a club record set in the Treble-winning year of 1999. MUTV, being MUTV, was full of Treble talk after the Villa game – at some point someone actually used the expression "with the greatest respect to Crawley Town" – yet instead of looking too far ahead this is the point where each match becomes a test of its own.

For instance: should United win at Wolves on Saturday they will set a record, and the attempt to emulate the achievement of Arsenal's Invincibles in 2003-04 will be on. One might argue that it is on already, but until the Villa game United were still in the shadow of their own record, not striking out over uncharted ground to haul in someone else's. However slightly, however subtly, the pressure will be raised on Saturday at Molineux, and United will be more than content to repeat their result of last March, a modest 1-0 win through a Paul Scholes goal when Wolves had done enough at least to earn a draw.

After the game, Sir Alex Ferguson gave his usual oration about gritty, unspectacular wins against unexpectedly difficult opponents being key to successful title campaigns, and when United followed up the Wolves result with much more fluent and handsome victories against Fulham, Liverpool and Bolton, they not only moved back to the top of the table they looked a shoo-in to finish the season in that position.

Then came Chelsea. The last Premier League game Manchester United lost, the one that bookends the start of their present unbeaten record, was at home to Chelsea on 3 April last season, when goals from Joe Cole and Didier Drogba inflicted a costly defeat on defending champions who had just lost Wayne Rooney to injury. The striker had been absent with a different problem in the 4-0 win at Bolton, but ankle damage sustained at the end of the Champions League quarter-final first leg against Bayern Munich cost his side dear. Not only did United proceed to surrender the title initiative with a tame and totally uninspired goalless draw at Blackburn following the Chelsea result, they have had to wait the best part of a year to have their best player back to something like his best.

If he can stay injury-free between now and the end of the season, the Rooney that traumatised Villa the other night should ensure the title returns to Manchester. "He was awesome," Gérard Houllier enthused. "He has everything, and playing like that United will be unstoppable."

Yes, but people were saying the same sort of thing this time last season. Rooney and United looked unstoppable then, too, right up to the point where what appeared a relatively minor injury threw everything off track and allowed Chelsea a way back in. Looking at the present table, with Chelsea 10 points in arrears, it seems impossible that the same thing could happen again, though as Carlo Ancelotti and John Terry keep saying, doing their best to turn up the psychological pressure on United a notch or two, the two sides still have to meet this season and two Chelsea wins would make life interesting. Even in that eventuality, United would still have to lose one more game to let Chelsea back into the race, and so far they have not lost any all season. It is possible that two defeats to Chelsea could open up a route for Arsenal instead, but less likely that Arsène Wenger's defence will permit an unbeaten run to the end of the season. Even if they have got both their games against Chelsea out of the way, they still need to play United, Spurs, Liverpool and Blackpool, not to mention two legs against Barcelona.

The European dimension is what tends to complicate matters when it comes to making predictions at this time of year. Not only does the pressure of big games in the Champions League knockout stage tend to have after-effects when the domestic programme is resumed, the disappointment of going out of Europe, of having a major ambition snatched away for another season, often takes a week or two to get over. So if Chelsea have bought Fernando Torres and David Luiz principally to take a tilt at the Champions League, having decided there is too much ground to make up in the league, their league form is likely to be unpredictable if they go out of Europe at a stage earlier than anticipated. Immediately after they were put out by Internazionale last season, Chelsea too wobbled at Blackburn. Like United, they could claim only a draw, and even though they regrouped impressively to secure the title with seven wins from their remaining eight games, they would not have been able to do so but for United unexpectedly slipping up.

With Torres in their ranks Chelsea will undoubtedly be feeling bullish about the rest of the season, though so too will United after evidence that Rooney is almost back to his old self. The advantage United have is that Rooney is not a newcomer to the club, and he has familiar colleagues such as Ryan Giggs, Dimitar Berbatov and Nani performing well around him. United also have Antonio Valencia and Park Ji-sung on their way back, not to mention reserves of the quality of Javier Hernández and Scholes, plus a settled and at present fit defence, so perhaps not too much ought to be read into their non-activity in the transfer window.

Chelsea, by contrast, have to introduce Torres to a new team and a different way of playing, and may have to change their normal set-up to accommodate him. Not only that, they face a Liverpool side on Sunday that Torres has just ensured will not be short of motivation. If the pressure, or at least the spotlight, will be on United in every remaining league game this season while they stay unbeaten, the task Chelsea have left themselves in the league is even more arduous. Until those two games against United come around, Chelsea have to ensure there are no further slips against lesser teams, if Liverpool will pardon the expression, to give the game away in advance. Sunday is now quite a test for Chelsea, the first of many. Arsenal, under nothing like the same pressure, may well be thinking they can exploit this situation and stay in touch until something gives, but unless something gives they still have ground to make up.

A personal hunch is that United, after last season's disappointment, have the league as their main priority this season. Ferguson has well and truly knocked Liverpool off their perch, but he would still dearly love to kick over the water bowl, smash the mirror and ring the ornamental bell before his watch is over. Roman Abramovich has always fancied the Champions League, and with one of the less daunting round-of-16 opponents in Copenhagen, Chelsea look as well placed as anyone, especially as Real Madrid under José Mourinho still appear a work in progress.

United would be happy with a 19th title, Chelsea over the moon with a European Cup, and Manchester City chuffed to little mintballs to finish in the top four. It all might happen, but what about Arsenal? They do not look like champions at the moment but maybe they could do everyone a favour – apart from neutral admirers of wonderful football the world over – by putting Barcelona out of Europe.